1. Field
This disclosure relates generally to manufacturing semiconductor wafers and more specifically, to manufacturing semiconductor wafers using systems having exhaust gases.
2. Related Art
When performing atmospheric pressure chemical vapor deposition (APCVD), byproducts from the chemical reaction may undesirably deposit on parts of the tool. These byproducts may fall onto the semiconductor wafer being processed and create dusting. The dusting effect decreases yield. Because any dusting is not detected until entire lots of wafers (e.g., 25 wafers per lot) are processed, the entire lots needs to be scrapped. Since APCVD is used typically to form interlevel dielectric layers (ILD), the lots have already undergone significant processing. Thus, scrapping wafers after APCVD wastes the time and money spent processing the wafers to this point. Furthermore, once it is determined that dusting has occurred, the tool must be taken out of production so that the cause of the dusting can be determined. The search for the cause and cleaning the tool may be time-consuming, which further decreases yield. Therefore, a need exists to decrease the negative impacts of dusting that occur during semiconductor manufacturing, such as when using APCVD.